HP 85020A Operating And Service Manual page 22

Operation
Model 85020A/B
CAUTION
Do not apply more than + 23 dBm RF power or
more than +10 volts DC into the 85020A/B.
If more than this power or voltage is
applied, the 85020 will be damaged.
CAUTION
Do not drop the 85020A/B or subject it to
mechanical shock, as this may cause
internal damage.
3-4. FEATURES
3-5. Features of the 85020A/B are shown in Figure 3-1.
3-6. CONNECTOR WEAR
CAUTION
Do not over-tighten the connectors of the
85O20A/B bridges. Excessive torque will
deform the mating surfaces. To mate type-N
connectors, always turn only the nut of
the male connector. Never turn the
Directional Bridge when making a
connection. Tighten by hand only.
3-7. Repeated connections will cause the connectors to become
worn, with a consequent degradation of performance. To extend the
life of the connectors, it is recommended that an adapter be used
on the test port in any application where some degradation of
directivity can be accepted. For the most accurate measurements, a
high quality adapter should be used, and the adapter should be
periodically replaced. High quality adapters (low insertion loss,
low return loss, stable in use, and durable) are necessary to
achieve accurate, repeatable measurements. Calibrate for
measurement using the same adapters and interconnect cables that
will be used during measurement. To ensure repeatable measurements
the adapters and cables must be clean, in good condition, and
properly tightened. Start with the best available adapters and
calibration standards then replace them when they become unstable.
Appropriate adapters are included in the 85023-series System
Verification Sets listed in Section I of this manual.
3-8. The input port connector and the test port connector are
part of the microcircuit bridge assembly. This assembly may be
replaced with a new or a rebuilt assembly. For information
3-2